Global Protect Clientless VPN loads a blank page for an application due to Javascript ES6 or newer used in the application
12124
Created On 05/25/23 10:14 AM - Last Modified 10/03/23 23:43 PM
Symptom
- When accessing the application via the Global Protect Clientless VPN, the website is loaded as a blank page.
- Sometimes the website is partially loaded and only some application content is missing.
- When using Chrome browser, under Settings > More tools > Developer tools > Console, error message similar to "The application contains JavaScript (ES6 or newer) that is not supported by the Palo Alto Networks JavaScript parser. The application might not work as expected" is displayed.
Environment
- Palo Alto Firewalls
- Supported PAN-OS
- GlobalProtect Clientless VPN Portal
Cause
- Clientless App configured uses Javascript ES6 or newer version.
- Javascript ES6 or newer is a web application technology not supported by GlobalProtect Clientless VPN JavaScript parser.
Resolution
- Javascript ES6 or newer is not supported by the Palo Alto GloablProtect Clientless VPN JavaScript parser:
- The workaround is to convert the application source code from JavaScript ES6 to ES5.
Additional Information
- Starting from GlobalProtect Clientless VPN version 98-260 (released on 2023/05/22), a catch for ES6 errors is included.
- That feature simplifies detecting JavaScript ES6 or newer in the application source code.
- Refer the error message in the screenshot below.